1 /* 2 * Copyright (c) 1983, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 /* from: static char sccsid[] = "@(#)lookup.c 8.1 (Berkeley) 6/9/93"; */ 36 static char *rcsid = "$Id: lookup.c,v 1.3 1994/03/07 05:05:33 cgd Exp $"; 37 #endif /* not lint */ 38 39 #include "defs.h" 40 41 /* symbol types */ 42 #define VAR 1 43 #define CONST 2 44 45 struct syment { 46 int s_type; 47 char *s_name; 48 struct namelist *s_value; 49 struct syment *s_next; 50 }; 51 52 static struct syment *hashtab[HASHSIZE]; 53 54 /* 55 * Define a variable from a command line argument. 56 */ 57 void 58 define(name) 59 char *name; 60 { 61 register char *cp, *s; 62 register struct namelist *nl; 63 struct namelist *value; 64 65 if (debug) 66 printf("define(%s)\n", name); 67 68 cp = index(name, '='); 69 if (cp == NULL) 70 value = NULL; 71 else if (cp[1] == '\0') { 72 *cp = '\0'; 73 value = NULL; 74 } else if (cp[1] != '(') { 75 *cp++ = '\0'; 76 value = makenl(cp); 77 } else { 78 nl = NULL; 79 *cp++ = '\0'; 80 do 81 cp++; 82 while (*cp == ' ' || *cp == '\t'); 83 for (s = cp; ; s++) { 84 switch (*s) { 85 case ')': 86 *s = '\0'; 87 case '\0': 88 break; 89 case ' ': 90 case '\t': 91 *s++ = '\0'; 92 while (*s == ' ' || *s == '\t') 93 s++; 94 if (*s == ')') 95 *s = '\0'; 96 break; 97 default: 98 continue; 99 } 100 if (nl == NULL) 101 value = nl = makenl(cp); 102 else { 103 nl->n_next = makenl(cp); 104 nl = nl->n_next; 105 } 106 if (*s == '\0') 107 break; 108 cp = s; 109 } 110 } 111 (void) lookup(name, REPLACE, value); 112 } 113 114 /* 115 * Lookup name in the table and return a pointer to it. 116 * LOOKUP - just do lookup, return NULL if not found. 117 * INSERT - insert name with value, error if already defined. 118 * REPLACE - insert or replace name with value. 119 */ 120 121 struct namelist * 122 lookup(name, action, value) 123 char *name; 124 int action; 125 struct namelist *value; 126 { 127 register unsigned n; 128 register char *cp; 129 register struct syment *s; 130 char buf[256]; 131 132 if (debug) 133 printf("lookup(%s, %d, %x)\n", name, action, value); 134 135 n = 0; 136 for (cp = name; *cp; ) 137 n += *cp++; 138 n %= HASHSIZE; 139 140 for (s = hashtab[n]; s != NULL; s = s->s_next) { 141 if (strcmp(name, s->s_name)) 142 continue; 143 if (action != LOOKUP) { 144 if (action != INSERT || s->s_type != CONST) { 145 (void)sprintf(buf, "%s redefined", name); 146 yyerror(buf); 147 } 148 } 149 return(s->s_value); 150 } 151 152 if (action == LOOKUP) { 153 (void)sprintf(buf, "%s undefined", name); 154 yyerror(buf); 155 return(NULL); 156 } 157 158 s = ALLOC(syment); 159 if (s == NULL) 160 fatal("ran out of memory\n"); 161 s->s_next = hashtab[n]; 162 hashtab[n] = s; 163 s->s_type = action == INSERT ? VAR : CONST; 164 s->s_name = name; 165 s->s_value = value; 166 return(value); 167 } 168